Abstract: A heat-resistant member of the present disclosure is formed of an alumina-based ceramic containing alumina crystals and a glass formed of Si, Ca, Mg, and O, and an area ratio occupied by the glass in an inner portion is larger than an area ratio occupied by the glass in the surface portion.

Abstract: A corrosion-resistant member according to the present disclosure includes a substrate that is composed of an aluminum-oxide-based ceramic and a covering layer that is composed of an O—Al—C layer that is located on the substrate.

Abstract: A corrosion-resistant member may include alumina ceramics containing ?-alumina and anorthite. The alumina ceramics may contain 0.4% by mass or more of Ca and Si in total in terms of CaO and SiO2, respectively, and a mass ratio of CaO/SiO2 may fall within a range of 0.5 to 2. Moreover, a ratio B/A of X-ray diffraction peak intensity B for (004) plane of the anorthite to X-ray diffraction peak intensity A for (104) plane of the ?-alumina in a surface of the alumina ceramics, may be 0.01 or more.

Abstract: A corrosion-resistant member may include alumina ceramics containing ?-alumina and anorthite. The alumina ceramics may contain 0.4% by mass or more of Ca and Si in total in terms of CaO and SiO2, respectively, and a mass ratio of CaO/SiO2 may fall within a range of 0.5 to 2. Moreover, a ratio B/A of X-ray diffraction peak intensity B for (004) plane of the anorthite to X-ray diffraction peak intensity A for (104) plane of the ?-alumina in a surface of the alumina ceramics, may be 0.01 or more.

Abstract: A corrosion-resistant member according to the present disclosure includes a substrate that is composed of an aluminum-oxide-based ceramic and a covering layer that is composed of an O—Al—C layer that is located on the substrate.

Abstract: A ferrite sintered body includes a crystal grain of a Ni—Zn ferrite and a grain boundary thereof, in which Ti is unevenly distributed in an outer region of the crystal grain, the outer region extending from an interface of the crystal grain to a length of 20% of a major axis of the crystal grain.

Abstract: The high-withstanding-voltage member includes an alumina sintered compact containing alumina as a main crystal. Furthermore, the alumina sintered compact exhibits a peak intensity of 5000 or less at a wavelength of about 330 nm when measured by a cathode luminescence method.

Abstract: There are provided a light-emitting element mounting substrate which exhibits high reflectivity, and a light-emitting module having high reliability and high luminance. A light-emitting element mounting substrate includes an alumina sintered body containing alumina crystal, zirconia crystal, and grain boundary phase, wherein an intensity ratio It/Im between a peak intensity It of tetragonal zirconia crystal at 2? ranging from 30° to 30.5° and a peak intensity Im of monoclinic zirconia crystal at 2? ranging from 28° to 28.5° measured by X-ray diffractometer using Cu-K? radiation, is less than or equal to 35 excluding 0. Further, a light-emitting element module includes the light-emitting element mounting substrate, and a light-emitting element mounted thereon.

Abstract: [Object] To provide a ferrite sintered body and a ferrite core each of which has a high permeability, and a coil component produced by winding a metal wire around the ferrite core. [Solution] A ferrite sintered body includes a crystal grain of a Ni—Zn ferrite and a grain boundary thereof, in which Ti is unevenly distributed in an outer region of the crystal grain, the outer region extending from an interface of the crystal grain to a length of 20% of a major axis of the crystal grain. The ferrite sintered body contains Fe, Zn, Ni, Cu, and Ti. When the total of components of Fe, Zn, Ni, and Cu in terms of oxides thereof is assumed to be 100% by mole, a composition of the ferrite sintered body is 48% by mole or more and 50% by mole or less of Fe in terms of Fe2O3, 29% by mole or more and 31% by mole or less of Zn in terms of ZnO, 14% by mole or more and 16% by mole or less of Ni in terms of NiO, and 5% by mole or more and 7% by mole or less of Cu in terms of CuO. The ferrite sintered body contains 0.

Abstract: The high-withstanding-voltage member includes an alumina sintered compact containing alumina as a main crystal. Furthermore, the alumina sintered compact exhibits a peak intensity of 5000 or less at a wavelength of about 330 nm when measured by a cathode luminescence method.

Abstract: There are provided a dielectric ceramic having a high Qf value in a relative permittivity ?r range of 35 to 45, and a small absolute value of a temperature coefficient ?f which indicates change of the resonant frequency in a wide temperature range from a low temperature range to a high temperature range, and a dielectric filter having the dielectric ceramic. A dielectric ceramic includes: a main component, molar ratios ?, ?, and ? satisfying expressions of 0.240???0.470, 0.040???0.200, 0.400???0.650, and ?+?+?=1 when a composition formula of the main component is represented as ?ZrO2.?SnO2.?TiO2; and Mn, a content of Mn in terms of MnO2 being greater than or equal to 0.01% by mass and less than 0.1% by mass with respect to 100% by mass of the main component.

Abstract: A ferrite sintered body having an improved strength and a noise filter including the same are provided. A ferrite sintered body includes 1 mol % to 10 mol % Cu on CuO basis, a spinel-structured crystal containing Fe, Zn, Ni, Cu and O as a main phase, and Cu compound particles present at a grain boundary, having an average particle diameter of 0.5 ?m to 10 ?m. The ferrite sintered body includes the Cu compound particles present at a grain boundary. It is thereby possible to suppress the grain growth of the crystals serving as the main phase to attain a morphology formed of fine crystals, and also inhibit the propagation of destruction of the grain boundary, thus making it possible to achieve a ferrite sintered body with an improved strength.

Abstract: There are provided a dielectric ceramic having a high Qf value in a relative permittivity ?r range of 35 to 45, and a small absolute value of a temperature coefficient ?f which indicates change of the resonant frequency in a wide temperature range from a low temperature range to a high temperature range, and a dielectric filter having the dielectric ceramic. A dielectric ceramic includes: a main component, molar ratios ?, ?, and ? satisfying expressions of 0.240???0.470, 0.040???0.200, 0.400???0.650, and ?+?+?=1 when a composition formula of the main component is represented as ?ZrO2.?SnO2.?TiO2; and Mn, a content of Mn in terms of MnO2 being greater than or equal to 0.01% by mass and less than 0.1% by mass with respect to 100% by mass of the main component.

Abstract: A ferrite sintered body having an improved strength and a noise filter including the same are provided. A ferrite sintered body includes 1 mol % to 10 mol % Cu on CuO basis, a spinel-structured crystal containing Fe, Zn, Ni, Cu and O as a main phase, and Cu compound particles present at a grain boundary, having an average particle diameter of 0.5 ?m to 10 ?m. The ferrite sintered body includes the Cu compound particles present at a grain boundary. It is thereby possible to suppress the grain growth of the crystals serving as the main phase to attain a morphology formed of fine crystals, and also inhibit the propagation of destruction of the grain boundary, thus making it possible to achieve a ferrite sintered body with an improved strength.

Abstract: A ferrite sintered body is composed of an oxide containing, as metal element, at least Fe and Zn and at least one selected from Ni, Cu and Mn. This sintered body contain Fe of 42 to 50 mol % in terms of Fe2O3, and Zn of 15 to 35 mol % in terms of ZnO. When the Zn concentration in the sintered body interior is taken to be 1, the Zn concentration in the surface vicinity is 0.8 to 12. This increases the surface resistance of the ferrite sintered body and lowers its core loss.

Abstract: A ferrite core comprising a sintered oxide containing at least 48.6 to 53.9 mol % of Fe on Fe2O3 basis, 12.3 to 35.2 mol % of Ni on NiO basis and 16.4 to 37.0 mol % of Zn on ZnO basis as metal elements, and contains a crystal phase comprising two or more kinds of solid solutions selected from NiFe2O4, ZnFe2O4 and FeFe2O4, wherein full width at half maximum of a diffraction peak, of crystal phase of which diffraction angle 2? is in a range from 34.6 to 36.4° as measured by X-ray diffraction analysis using Cu—K? beam, is 0.4° or less.

Abstract: A ferrite sintered body is composed of an oxide containing, as metal element, at least Fe and Zn and at least one selected from Ni, Cu and Mn. This sintered body contain Fe of 42 to 50 mol % in terms of Fe2O3, and Zn of 15 to 35 mol % in terms of ZnO. When the Zn concentration in the sintered body interior is taken to be 1, the Zn concentration in the surface vicinity is 0.8 to 12. This increases the surface resistance of the ferrite sintered body and lowers its core loss.

Abstract: A ferrite core comprising a sintered oxide containing at least 48.6 to 53.9 mol% of Fe on Fe2O3 basis, 12.3 to 35.2 mol % of Ni on NiO basis and 16.4 to 37.0 mol % of Zn on ZnO basis as metal elements, and contains a crystal phase comprising two or more kinds of solid solutions selected from NiFe2O4, ZnFe2O4 and FeFe2O4, wherein full width at half maximum of a diffraction peak, of crystal phase of which diffraction angle 2? is in a range from 34.6 to 36.4° as measured by X-ray diffraction analysis using Cu—K? beam, is 0.4° or less.